Khan.scratchpad.disable(); To move up to the maestro level in his piano school, Ben needs to master at least $170$ songs. Ben has already mastered $19$ songs. If Ben can master $7$ songs per month, what is the minimum number of months it will take him to move to the maestro level?
Explanation: To solve this, let's set up an expression to show how many songs Ben will have mastered after each month. Number of songs mastered $=$ $ $ Months at school $\times$ Songs mastered per month $+$ Songs already mastered Since Ben Needs to have at least $170$ songs mastered to move to maestro level, we can set up an inequality to find the number of months needed. Number of songs mastered $\geq 170$ Months at school $\times$ Songs mastered per month $ +$ Songs already mastered $\geq 170$ We are solving for the months spent at school, so let the number of months be represented by the variable $x$ We can now plug in: $x \cdot 7 + 19 \geq 170$ $ x \cdot 7 \geq 170 - 19 $ $ x \cdot 7 \geq 151 $ $x \geq \dfrac{151}{7} \approx 21.57$ Since we only care about whole months that Ben has spent working, we round $21.57$ up to $22$ Ben must work for at least 22 months.